Tear line construction for paperboard cartons



o. w. STONE 3,036,755

TEAR LINE CONSTRUCTION FOR PAPERBOARD CARTONS May 29, 1962 OriginalFiled Oct. 25, 1957 INVENTOR ORISON W- STONE ATTORN Y5 United StatesPatent ()fihce 3,@35,755 :Patentecl May 29, 1962 3,036,755 TEAR LINECONSTRUCTION FGR PAPERBOARD CARTUNS Orison W. Stone, Valley Cottage,N.Y., assignor to Continental Can Company, Inc., New York, N.Y., acorporation of New York Original application Oct. 25, 1957, Ser. No.692,431, now Patent No. 3,004,697, dated Oct. 17, 1961. Divided and thisapplication Oct. 16, 1961, $91. No. 145,081

3 Claims. (Cl. 229-51) The invention relates to improvements in theconstruction of tear lines, and more particularly to the configurationand arrangement of tear lines made up of a succession of spaced outlines knifed into, or through, the paperboard stock. My invention isuseful wherever tear 'lines are employed: for example, along the edge ofa cover or cover opening, around the sides of a coupon section, acrossor around the body of a carton to assist in opening the carton or toform a hinged cover at one end, or along the edges of a tab for apouring opening or a re-closure, and so on. This application is adivision of my copending application Serial No. 692,431, filed October25, 1957, now Patent No. 3,004,697, granted October 17, 196 1.

A common difficulty with tear lines is that the line of tearing willoften wander away from the cuts or perforations which are supposed tocontrol the direction, or directions, of tear. Sometimes a succession ofcut lines arranged at an angle to the line of tear will be used, but thetrouble with this is that there is a tendency to tear away to theoutside of the forward ends of such cuts. What may happen is that thepaperboard stock will begin to tear at the end of a cut, the line oftear continuing from this point to the outside of its intended course,in which circumstance the actual tear will miss the succeeding cutaltogether. Once this occurs, the tear goes out of control and may missa whole series of cuts before getting back on the beam.

I have found that a much more certain control of the direction andcourse of actual tearing can be secured by arranging a succession ofspaced out lines at an angle to the line of tear, using cut lines whichare hooked around in the general direction of the line of tear. Withthis construction a tear which begins to Wander to either side of theforward end of a cut will nevertheless be quite certain to cross thepath of the succeeding cut. The effect might be described as one inwhich wandering of the tear is corrected within the space of twosucceeding cuts. Thus the course of tearing is corrected at closeintervals, the correction being made quite certain by reason of thespecial configuration and arrangement of the cuts. The cuts which arehooked at their forward ends (forward in relation to the direction oftearing) and their rearward ends may be described as having the generalconfiguration of Ss or reversed Ss. Here we might have Ss along one tearline and reverse Ss along a second tear line spaced from, and perhapsparallel to the first. The tearing action beginning at the hook at theforward end of the S-cut will be quite certain to cross the path of thenext succeeding cut. This is the sine qua non of a perfectly controlledtear line.

With reference to the drawings I shall now describe the best modecontemplated by me for carrying out my invention.

FIG. 1 is a perspective view of a carton to illustrate how my improvedtear line construction can be applied to a tear-out strip extendingaround one or more sides of the carton.

FIG. 2 is an enlarged view of a section of the tearout band and adjacentportions of the side wall of the carton of FIG. 1.

In the construction shown, there are spaced tear lines 12 and 13 eachcomprising a succession of spaced cut lines 8 arranged at an angle tothe line of tear and having hooked forward ends 9 and rearward ends 11.Notice that the ends 9 are hooked around in the general direction of theline of tear; and that when tear-out strip 14 is broken out and awayfrom the sides of the carton, and is pulled up and over as shown in FIG.2, the hooked ends 9 are effective to control the course of tearing sothat it will cross the path of each succeeding cut line. This will beexplained more exactly with reference to FIG. 2 in which the arrow arepresents, diagrammatically, the direction of pull.

The cut lines 8 have been described as having ends 9 hooked around inthe general direction of the line of tear. These cut lines arecharacterized by the fact that the end portions 9 of each is turned intoward an adjacent end portion of the succeeding cut line. As shown inFIGS. 1 and 2, the opposite end portion 11 of each cut line is turned inthe opposite direction. This results in a tear line construction 12which may be described as comprising a succession of similarly disposedspaced cut lines of the general configuration of Ss or, defining S asbeing inclusive of its mirror image, this will include also the tearline construction 13 in which the Ss are reversed. In either case 12 orcase 13, the forward end 9 of each cut is hooked around in the generaldirection of the line of tear and is turned in toward an adjacent endportion of the succeeding cut lines while the opposite end portion ofeach cut is turned in the opposite direction. Thus the parallel spacedtear lines 12 and 13 of the construction shown in FIG. 2 which arecomplementary are utilized to provide a tear-out strip 1-4 extendingaround three sides of the carton.

The terms and expressions which I have employed are used in adescriptive and not a limiting sense, and I have no intention ofexcluding such equivalents of the invention described, or of portionsthereof, as fall within the scope of the claims.

I claim:

1. Tear line construction for paperboard cartons which comprises asuccession of similarly disposed spaced cut lines of the generalconfiguration of Ss, 8 being defined as inclusive of its mirror image,each end portion of each of said cut lines being directed toward theadjacent end portion of the succeeding cut line.

2. Tear line construction according to claim 1 in which there are twospaced tea-r lines each comprising a succession of cut lines as defined,the cut lines comprised in one of the tear lines being of the generalconfiguration of Ss, and those of the other tear lines being of thegeneral configuration of Ss as seen in mirror image.

3. In a carton made of paperboard stock, a tear line which comprises asuccession of similarly disposed spaced cut lines of the generalconfiguration of Ss arranged along a line of tear and in which thehooked portions forming the end portions of the Ss are located at theforward and rearward ends of the cut lines (i.e. forward in relation tothe direction of tearing) with the ends of each hooked portion extendingat an angle of approximately forty-five degrees to the line of tear andin line with the adjacent end of the hooked portion adjacent thereto.

References Cited in the file of this patent UNITED STATES PATENTS2,285,542 Tasker June 9, 1942 2,680,558 Mai June 8, 1954 2,752,037 VogtJune 26, 1956

